In the midst of last week's Democratic presidential debate in South Carolina, the candidates were asked by the moderator, NBC News' Brian Williams, to address popular perceptions about their weaknesses. Each candidate confronted the "elephant in the room" concerning their candidacy — from the level of Barack Obama's commitment to practicing the new kind of politics he preaches to Joe Biden's "uncontrolled verbosity."

If there were a few elephants running around the debate stage for those candidates, those making an appearance at tonight's Republican debate in California are likely to be much larger in size and more numerous in number. As 10 GOP presidential candidates gather at the Ronald Reagan Presidential Library to make the case for their candidacies, the large animals standing around that nobody wants to talk might look more like prehistoric wooly mammoths than modern-day pachyderms.

The biggest "mammoth in the room" tonight undoubtedly will be the two-headed problem for these candidates of President Bush and the war in Iraq — both unpopular among the majority of Americans yet still supported by Republican primary voters who will pick the nominee. Even if the location for this gathering were on the moon, the name Reagan would be invoked far more than that of the past two Republican presidents, and we can fairly expect a spirited competition for most mentions of the name.

As it did for much of the Democratic debate, Iraq is likely to dominate much of this discussion. These Republicans continue to be supportive of the war in varying degrees even as they have sought ways to distance themselves from it by criticizing the manner in which it has been conducted. Don't look for much different this evening, as these candidates will try to find ways to turn the discussion away from events in Iraq to bigger themes of terrorism and national security.

Despite an unwillingness to outwardly break with their president on those issues, each of the Republican candidates — especially the three perceived as top tier — have differences with one another, and with sizable chunks of their own party, that are almost certain to produce some fireworks.

Rudy Giuliani, the former mayor of New York City, is a puzzling front-runner by traditional measures. He leads in most national polls, both against his Republican competitors and the potential Democratic nominees. Yet his views on issues ranging from abortion to gay marriage and gun control are hardly what the nation has come to expect from a Republican candidate for president. He will certainly be prepared to answer those questions, but is he prepared for some possible sharp elbows by others in the field who may throw them in a bid to attract the eye of social conservatives?

As the one-time favorite, John McCain has fallen on tough times so far in this campaign. More than anyone else, he has become almost as closely associated with Iraq as the president. That's something which would be an enormous benefit in other circumstances — but has turned into a real liability as the war has grown more unpopular. It should help endear him to Republicans as a loyal fighter for the cause, but many in the party have not forgiven him for perceived sins like his quest to enact campaign finance reform, his initial opposition to the Bush tax cuts and for being all-too-cozy with the Washington media establishment. Experience and a compelling life story remain McCain's calling cards and those won't change tonight. He'll also have an opportunity to address the issue of his age in a compelling manner in this forum. If elected, McCain would be the oldest president to take office when sworn in, a distinction currently held by Reagan.

If anyone would have tried to convince most political observers four years ago that a former governor of Massachusetts would be a front-runner for the Republican nomination in 2008, they would have been sent to an institution. But Mitt Romney's impressive start to his campaign, at least in terms of his ability to raise massive amounts of money and gain party endorsements, is making it a reality. But in cutting a path from winning the Bay State to running for the Republican nomination, Romney has undergone some dramatic transformations. Like Giuliani, Romney certainly will be ready to answer questions about his shifting positions, but he could escape direct attacks if the front-runner becomes a target.

One of the great ironies of this field is that most of the seven remaining candidates more closely resemble what we've come to think of as solid Republicans — social and fiscal conservatives comfortable in the homes of evangelical activists and on the air with conservative talk-show hosts. Kansas Sen. Sam Brownback and former Arkansas Gov. Mike Huckabee are two conservatives in particular who were once viewed as potential favorites of activists but have yet to find ways to break through? Will tonight be that chance?

Rep. Duncan Hunter was the first to announce his 2008 candidacy and has won or finished near the top in some early straw poll contests but has gained little traction otherwise. Former Virginia Gov. Jim Gilmore and former Wisconsin Gov. Tommy Thompson jumped into the race relatively late and are looking to make a statement in the small hamlets of states like Iowa. Rep. Ron Paul has potential to be the Mike Gravel of this crowd with his opinion that the party has strayed too far from its more-libertarian ideals.

Colorado Rep. Tom Tancredo's candidacy itself represents a very large elephant in the room for these candidates. A longtime crusader against illegal immigration, Tancredo shines a spotlight on an issue many of them would just as soon not highlight. His message of getting tough on the immigration issue represents the sentiments of a loud and not-so-small wing of the party that favors much tougher border control and expulsion of the estimated 12 million illegal and undocumented aliens already in the United States.

These Republicans oppose any immigration reform that allows for a path to citizenship for anyone in the country illegally — something included in proposals put forward by both President Bush and McCain. But a sizable number within the party favor such policies on grounds that the labor supplied by immigrants is necessary to many industries and also a large-scale displacement is both impractical and inhumane.

Another mammoth in the room, one less likely to be discussed, is the clear unease of not a few Republicans about the current field. Non-candidates like former House Speaker Newt Gingrich and former Sen. Fred Thompson perform near the top in polls including their names, in some cases even beating candidates like Romney. The more party leaders speak about the possibility of an expanded field, the more diminished the current crop begins to look. A big question for tonight is whether they can start putting those concerns to rest.

Last week, some critics and campaign operatives complained that these debates are of little use in helping voters to take measure of the candidates seeking to become leader of the free world. Ninety minutes divided between eight (in this case 10) candidates, not to mention the moderator, yields only 60-second canned answers or non-answers to complicated issues. True, it may seem like a lot of commotion for relatively little return, but it's early in the process. We're almost certain to become more familiar with these candidates through events like this, and that can't be a bad thing.— Vaughn Ververs

The Most Watched Woman In The Room: When Ronald Reagan's name is invoked in tonight's debate, don't be surprised if those in the room turn their attention to former First Lady Nancy Reagan, who will be in attendance at her late husband's presidential library.

While she certainly won't offer any endorsements, Nancy Reagan will still be watched for any eyebrow raise, smile or gesture that might offer the slightest hint as to which candidates she might favor — winning her approval might be the next best thing to an endorsement from the Gipper himself.

But her presence could create an awkward moment for those on stage if the issue of embryonic stem cell research is raised. She has broken with the GOP establishment in supporting expanded federal funding for the research, which supporters say could lead to treatments for the Alzheimer's disease her husband suffered from after his presidency.— David Miller

Obama's Campaign Quandary: The Democratic blogging community has had a mixed reaction to the controversy over Barack Obama's MySpace profile, which the campaign seized control of after being unable to strike a deal with the unpaid supporter who originally created the page.

Some believe the site's original creator, Joe Anthony, was wrong to request any payment for volunteer work. Others believe the Obama campaign is hypocritical for taking over the page while talking so much about empowering Americans.

Obama has acted fast to smooth over the dispute. First, he personally called Anthony to discuss the awkward handling of the situation. Today, in a move that is sure to be applauded by the party's netroots, Obama asked Democratic National Committee Chairman Howard Dean to make videos of DNC-sanctioned presidential debates available for free online use. "Rather than restricting the product of those debates, we should instead make sure that our democracy and citizens have the chance to benefit from them in all the ways that technology makes possible," the letter reads.

Give the campaign credit for acting fast in an attempt to quell any uproar. After John Edwards, Obama is probably the most popular Democrat in the blogosphere. Alienating that group could have cost him a lot in organizing power.

But there are still questions raised by the incident that the Obama campaign will have to address in the coming months. Obama has tried to create an image of an unconventional candidate running an unconventional, people-powered campaign. Such a strategy has its benefits, especially when running against an establishment candidate like Hillary Clinton.

However, it also has substantial risks, as the MySpace controversy demonstrates. Obama's campaign faces the challenge of staying on message. But the message itself — that of a movement with a bottom-up power structure — makes that task all the more difficult. How Obama manages that dilemma could be a key storyline as the campaign continues.— David Miller

A Reason For GOP Optimism: Times are tough for the Republican presidential candidates, but a new poll out of Quinnipiac University gives them some cause for optimism. In matchups between the various frontrunners in both parties, the worst the Republicans do is a tie.

Specifically, Rudy Giuliani topped Hillary Clinton by 9 percentage points, though he had a smaller 3 percentage point edge over Barack Obama. John McCain bested Clinton by 5 percentage points, though he tied with Obama, with both having the support of 42 percent of respondents. (In case you were curious, non-candidates Al Gore and Fred Thompson both lost when paired against an opponent from the other party. Running against each other, Gore beat his fellow Tennessean by 10 percentage points.)

If things are going so badly for the GOP, shouldn't Clinton and Obama — or any other mainstream Democrat — trounce Republicans in a poll like this? Well, not necessarily. Clinton's problem is likeability: The poll showed 46 percent of respondents said they had an unfavorable opinion of her, compared with 44 percent who liked her. Obama's problem is anonymity: More than one-third of respondents said they didn't know enough about him to form an opinion.

The good news for Obama is that those who have heard of him like him. Only 18 percent of respondents viewed him unfavorably.— David Miller

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